She was a member of Meath County Council for the Dunshaughlin electoral area from 2009 to 2011. She was a member of the Oireachtas committees for Health, Finance, and the implementation of the Good Friday Agreement during the 31st Dáil. She was also a member of the Constitutional Convention, and was the Chairperson of the Fine Gael committee for health and children. In January 2013, her IT consultancy company went into liquidation with debts of €280,000, including €60,000 due to the Revenue Commissioners. In May 2015, following the claims of IRA involvement of the cover-up of sexual abuse by Máiría Cahill, she was provided with names of a number of alleged abusers which she passed on to the Gardaí who are investigating the issue. She was re-elected to the Dáil on 26 February 2016. She was appointed to the new Dáil reform committee on 22 March of that year. She was appointed Government Chief Whip on 6 May 2016. In July 2017, Doherty confirmed that she had lodged a complaint with gardaí against political blogger and academic Catherine Kelly. Kelly said that she was cautioned by gardaí about her social media posts and online articles which referenced Regina Doherty. In the Dáil it was stated that a US based academic experienced a "sinister and chilling experience" in an Irish airport. In September 2017, it was revealed that she is going to repay an "unlawful" allowance of €15,800 that she received as Chief Whip in direct contravention of the law which states that “no allowance can be paid to a party whip if the person is a Minister or Minister of State”.